jcgp.backend.population

Interface Mutable

All Known Implementing Classes:

Node, Output

public interface Mutable

Mutable declares the expected behaviour of any part of a chromosome that is mutable, more specifically nodes or outputs. Inputs are not mutable since they don't have connections or functions.

This interface provides a way to deal with mutable elements generically without having to specify whether they are nodes or outputs. When mutating a mutable, mutate() is guaranteed to perform a fair mutation.

Author:

Eduardo Pedroni

Method Summary

Modifier and Type	Method and Description
boolean	copyOf(Mutable element) Asserts if the specified element is a copy of the elements this is called on. This method returns true if and only if: the elements being compared are not the same instance; the connections of the compared elements are not the same instance; the elements have the same function (in the case of Node); the grid position of the elements themselves are the same; the grid position of all equivalent connections are the same; The relationship computed by this method is: symmetric: a.copyOf(b) == b.copyOf(a); not reflexive: a.copyOf(a) returns false; not transitive: if a.copyOf(b) is true and b.copyOf(c) is true, a.copyOf(c) is not necessarily true since it is possible that a == c.
void	mutate() This method performs an arbitrary mutation on the Mutable.

Method Detail

mutate

void mutate()

This method performs an arbitrary mutation on the Mutable.

In the case of nodes, this chooses to mutate a function or connection fairly, and carries out the required mutation by using the node's own reference to chromosome.

In the case of outputs, this simply picks a random connection to serve as the source - any connection is allowed.

copyOf

boolean copyOf(Mutable element)

Asserts if the specified element is a copy of the elements this is called on.
This method returns true if and only if:

• the elements being compared are not the same instance;
• the connections of the compared elements are not the same instance;
• the elements have the same function (in the case of Node);
• the grid position of the elements themselves are the same;
• the grid position of all equivalent connections are the same;

The relationship computed by this method is:

• symmetric: a.copyOf(b) == b.copyOf(a);
• not reflexive: a.copyOf(a) returns false;
• not transitive: if a.copyOf(b) is true and b.copyOf(c) is true, a.copyOf(c) is not necessarily true since it is possible that a == c.

Parameters:

element - the mutable element to compare to.

Returns:

true if element is a copy of this element.